T8531A/T8532 Agere Systems, Inc., T8531A/T8532 Datasheet - Page 46

• Manufacturer Part Number: T8531A/T8532
• Description: Multichannel Programmable Codec Chip Set
• Manufacturer: Agere Systems, Inc.

Codec Chip Set
Applications
Figure 13 shows the complete SLIC schematic for interfacing to the Agere L9310G Line Interface and Line Access
circuit. All ac parameters are programmed by the codec. Note, this codec differentiates itself in that no external
components are required in the ac interface to provide a dc termination impedance or for stability. For illustration
purposes, 2.2 Vrms PPM injection was assumed in this example and hybrid meter pulse rejection is used. Also, this
example illustrates the device using the battery switch with multiple battery operation and programmable overhead,
current limit and loop closure threshold.
46
PROGRAMMABLE
FUSIBLE
FUSIBLE
OR PTC
OR PTC
VOLTAGE
50
SOURCE
50
V
FROM
BAT
SECONDARY
PROTECTOR
SECONDARY
PROTECTOR
180 V—330 V
100 V—130 V
RINGING
SOURCE
400
1 M
R
R
(continued)
RTF
S1
0.1 F
C
RTS
R
LCTH
V
Figure 13. Line Card Solution Using the L9310G SLIC
BAT2
V
PWR
T
R
RSW
RTS
PR
PT
OVH (OVERHEAD = 9.2 V for 2.2 Vrms PPM)
V
LCTH (THRESHOLD = 11 mA)
BAT2
RING
PROG
CV
RING
0.1 F
BAT2
CF1
/
V
(I
V
BAT1
LIMIT
0.1 F
BAT1
CV
0.1 F
C
= 25 mA)
BAT1
F2
BGND
CF2
V
CC
V
CC
0.1 F
(GAIN OF 2)
RESET
C
L9310G
CC
AGND V
MICROPROCESSOR
TESTLEV
A
V
DD
DD
PER-LINE
TO/FROM
0.1 F
C
DD
DGND
TESTSIG
ICM
D
PPMOUT
TRGDET
PPMIN
VITR
R
R
V
VTX
TXN
V
LCF
FB2
FB1
ITR
TXI
CVP
CVN
REF
REF
0.1 F
0.01 F
C
C
C1
PPM
R
17.4 k
R
6.49 k
C
0.1 F
PPM
GX
TX
301 k
R
GENERATION
2.2 Vrms at T/R
VREF
0.7 Vrms for
RAMPED
PPM
Agere Systems Inc.
VRTX
VTX
VRP
VRN
T8532
May 2001
0500 (F)